This file defines months/special days in year name and their length in days.
First column is just month/day number on the list.
2nd column is the duration in days.
3rd column is the strref to dialog.tlk to name of the month/day.
This table is apparently not used in PSTEE.

In PSTEE we have:

2DA V1.0
0
      DAYS  NAME
0     28    15934
1     28    15935
2     28    16042
3     28    15936
4     28    15938
5     28    15942
6     28    15944
7     28    15945
8     28    15947
9     28    15948
10    28    15956
11    28    15957
12    28    15964